[OT] DMA Channel Available to Linux?

[7mgte]

I have been going over various resources on how to write Linux device drivers.  There are functions for managing DMA channels.  However, what is not clear is whether there is actually any DMA hardware available on a PC motherboard to use.  Some other sources lead one to believe there used to be a DMA engine back in the days of motherboards with ISA buses.  However, today's PCI based motherboard designs leave DMA implementation to the plug-in card designer.

Where all this comes from is a project we are working that needs to transfer data from the PC to a memory mapped card which does not have DMA.  

Pointers to references, suggestions, observations, etc will be greatly appreciated!

Thanks!

Don